From mboxrd@z Thu Jan 1 00:00:00 1970 From: Isaac Huang Date: Thu, 08 Oct 2009 15:42:25 -0400 Subject: [Lustre-devel] using LST for performance testing In-Reply-To: <4AC23B21.2030207@cray.com> References: <4ABBD78E.50506@cray.com> <20090928173554.GA4911@sun.com> <4AC23B21.2030207@cray.com> Message-ID: <20091008194225.GX4767@sun.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lustre-devel@lists.lustre.org On Tue, Sep 29, 2009 at 11:51:45AM -0500, Nic Henke wrote: > ...... > > The test servers concurrently posts one passive buffer for each > > request, so for each test request there's one LNetMDAttach and one > > unlink operation and both operations need to grab the one big > > LNET_LOCK therefore it could be possible that the server CPU becomes a > > bottleneck before the network could be saturated. The solution is to, > > instead of one request per buffer, post one big buffer that could > > accommodate multiple requests to amortize the per buffer processing > > costs. > > > If we added timestamps to the data, the processing time & buffer sizing > would be less of an issue - it wouldn't factor into the accuracy of the > numbers are are gathering. Probably not. The timestamps affect only the stat gathering RPCs which should be far out numbered by the test RPCs (loop x concurrency x test_client_count, for each test server). Isaac